It mostly makes a difference in term of whether he started to shoot at people because of some religious cause (as ISIS and most Jihadis have), OR he just flipped because he had mental, emotional or other problems, that weren’t connected to religion at all. The two are not always related.
Remember, Andres Behring went on a rampage in 2011 in Norway, killing 8 people by detonating a bomb in a van and shooting 69 people. Was he a “secular moderate muslim” or connected to any particular religion?
One thing appears clear already. He did not just flip. Nor did the killer in Nice "just flip". In both cases it appears some long term planning took place. In Sonboly's case he needed to acquire the gun, and also set up a fake Facebook page. So it is not something that happened over-night.
Now, it does not necessarily have to be connected to his religious or political faith (as with Anders Breivik) but the witness satement from the MacDonalds restaurant where he started his rampage, makes it very likely it is.
Did he yell allah ackbar?
And his killings WERE ideologically motivated. He targeted the children of Left Wingers.
From the article linked in #5:
Reports also suggest that the teenager changed his WhatsApp profile picture to infamous mass murderer Anders Breivik, who killed 77 people in Norway on 22 July, 2011.
Mr Andrae said there was an ‘obvious’ link between the shocking massacre on Friday and the fifth anniversary of Breivik’s attacks.
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